How Cassini Will Begin Its Date with Death on Saturn | Hacker News Reader

How Cassini Will Begin Its Date with Death on Saturn

nytimes.com

64 pointsmy_first_acct27 comments

Pardon my ignorance, but what is the point in sending the Cassini probe to burn up in Saturn's atmosphere? Are there no more useful observations it can make, and if there isn't right now, can it not just be parked in orbit around Saturn until later? I mean, just the launch vehicle itself cost $422 million according to Wikipedia.

Probably some sort of space protection treaty once they are done funding ground operations. I too am dismayed about crashing perfectly functioning science vehicles.

This looks like the principle "States shall avoid harmful contamination of space and celestial bodies." Presumably crashing into a gas giant is considered less harmful than polluting orbit. Source: http://www.unoosa.org/oosa/en/ourwork/spacelaw/treaties/intr...

How is having a vehicle that is hibernating and can be contacted with considered polluting the orbit? It's not like it is debris. I would see this as in fact the opposite, I would see it as the first step to colonization. Having autonomous outposts all around the solar system, orbiting various celestial bodies. Build a meshnet with them.

It's functional now. After 30 years in hibernation? Who knows. The potential science value of life on another body in our solar system is so great, it's not worth the risk.

The science Cassini is capable of collecting will pale in comparison to whatever we'll have in orbit in 30 years anyway.

One thing to remember is that any probe past Mars is almost certainly going to use an RTG over solar panels. This means that you will always have an exponentially decaying power supply (wattage goes down over time if you use it or not). This is how voyager was powered, and because of the power drain, they had to turn off more instruments as time goes on.

It's not like its orbit is stable in an environment like that. Eventually it's going to collide with something due to lack of fuel for maneuvering burns.

The article didn't say, but off-hand I would guess it's for the same reason they crashed Galileo into Jupiter (https://en.wikipedia.org/wiki/Galileo_(spacecraft)), namely to avoid any possibility of contaminating one of the moons (see https://en.wikipedia.org/wiki/Life_on_Titan) with life (e.g., bacteria) from Earth.

This is correct, the probe was too large to sterilize, and they want to avoid any possibility of contaminating Enceladus.

http://www.spacesafetymagazine.com/space-exploration/extrate...

That seems like a really poor reason for doing it seeing as Cassini carried Huygens with it -- which already landed on Titan over 10 years ago.

Flying a mission to intentionally study a moon is a bit different than accidentally contaminating it while getting no useful data. Titan isn't a likely candidate for contamination anyway and if we ever do find life there it is likely to be distinguishable from Earth life. Enceladus, on the other hand, is one of the likeliest places for Earth-like life in our solar system and much more succeptible to contamination.

Since the orbiter is out of fuel and will eventually crash into something, Saturn makes the most sense.

Are we not actively trying to terraform Mars? Why is "life contamination" seen as a problem for our solar system rather than a goal?

The days of colonialism, when Europeans showed up on foreign shores, killed the natives, and claimed the land as their own, are over.

*barfs

  are over

You mean like in Iraq, Afghanistan, Syria, and Israel?

Those are proxy wars and/or puppet governments, which is a different thing to colonisation. There is somewhat more regard for the rights of the native inhabitants than in the past.

If we ever find alien life, the Outer Space Treaty prohibits colonisation in the sense we're using here. Of course this is a very easy treaty to sign up to at this point in our development of space travel. If space travel ever becomes cheap enough to enable exploitation of resource on distant planets I imagine those laws will see some amendments.

So, why is it a goal to send humans there? Humans breathe out bacteria constantly and will guarantee contamination of Mars.

> Are we not actively trying to terraform Mars?

> Why is "life contamination" seen as a problem for our solar system rather than a goal?

Because you'll not be sure if eventual life that you found there comes from Earth equipment or was there in the first place

So, why is it a goal to send humans there? Humans breathe out bacteria constantly and will guarantee contamination of Mars.

I don't understand why we're doing this. They will eventually be contaminated in the next 500 years and that's not long evolutionarily speaking. As tech becomes cheaper and the third world starts breaking into the "modern era", we'll have more failed satellites embedded in the sides of every moon in the solar system. And NASA legitimately struggles to make these devoid of life. An exuberant little nation punching a little above its weight category certainly won't.

That still means we have 500 years to find legitimate non-terrestrial life.

Exactly. Also, In 500 years, it may be possible/economical to sterilize large bodies before sending them to outer space.

I think its a good idea that NASA (and other space agencies) are so careful about this. I wouldn't want any life (or the traces of past life) to be wiped out by organisms from earth.

See: https://saturn.jpl.nasa.gov/mission/grand-finale/why-end-the... and https://en.wikipedia.org/wiki/Cassini–Huygens_retirement

Cassini have used up almost all its fuel, so it cannot be controlled for much longer.

Cassini gave us so much amazing information. Lakes on Titan, giant geysers on Encaladus from an underground ocean, a moon that looks like the death star, our first lander on an object further than Mars, etc.

Doesn't Cassini have some nasty nuclear fuel? Probably best to put it where no one could get at it.

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